Building an online course[1] has been one of the easiest ways to make money in my personal experience. Other things I've tried building: SaaS, Trades business, Freelancing business. I've made over $8k since I launched last month and it's been a great stepping stone into other ideas. The main problem I see going forward is getting consistent traffic. Building the course was the "easy" part and now I'm focusing hard on…
Please correct me if I'm wrong, but you got to the frontpage of HN the first time you posted your site which presumably generated the bulk of that 8k, right? If you hit the jackpot (I.e. front page of HN) on your first try, yes it's going to feel like it's super easy to make money off building a course.
Lots of traffic also came from: reddit, word of mouth, FastAPI sponsorship, twitter, and indiehackers.